查询词典 signal to noise ratio

In the intersatellite coherent optical communication, the vibration of a satellite will lead to a pointing error of transmitting and receiving antennas, which will decrease the signal-to-noise ratio and increase the bit error rate. In this paper, the Rayleigh distribution is taken as the pointing error model caused by satellite vibration, and PSK homodyne communication scheme is used as an example to analyze the influence of the satellite vibration on the system instantaneous BER and average BER. The simulation calculation result of BER is given.

针对星间相干激光通信中卫星平台的振动造成发射天线和接收天线的瞄准角误差，使系统信号信噪比下降，误码率增加，该文以瑞利分布作为振动造成的瞄准角误差模型，结合高斯本振光和艾里信号光外差检测模型，以PSK零差通信体制为例分析卫星振动对系统的瞬时误码率和平均误码率的影响，给出误码率仿真计算结果。

Experiments on synthetic images with low signal-to-noise ratio images and nature images show good performmance and robust of the approach, especially it's capable to capture the discontinuous boundary and move snakes into boundary concavities.

对人工合成的低信噪比图像及自然图像的实验表明，本文方法性能良好，工作稳定，具有较强的处理边缘不连续及进入凹形边缘能力。

These results suggest that when the demagnetizing energy of soft layer is unavoidablethe application of high Ms soft layer can help to decrease the switching field,maintainthe thermal stability,improve the uniformity,reduce the thickness of interlayer andtotal recording layer,and will not worsen the signal to noise ratio.

研究结果说明当软磁层的退磁能无法避免时，使用较大饱和磁化强度的软磁层有利于降低矫顽力，保持热稳定性，提高介质的均匀性，减小中间层和记录层的厚度，并且对信噪比没有不良影响。

In the three dimensional seismic survey research process to HuoJitu well field in DaLiuta coal mine, it used weakness before superimposes、three dimensional after superimposes weakness followed with noises and other technics to dispose with the primary earthquake section planes, which enhancing three dimensional earthquake data body signal-to-noise ratio.

在对大柳塔煤矿活鸡兔井田进行三维地震勘探研究过程中，对原始地震剖面采用叠前面波衰减、三维叠后随机噪音衰减等新技术加以处理，提高地震三维数据体的信噪比。

In the third chapter, the problem of WCDMA network capacity has been introduced from the point of wireless planning. Through the analysis on WCDMA system load factor, the interference level allowance as well as the signal to noise ratio, the relation among WCDMA system capacity, coverage and the grade of service is demonstrated. The method to compute system parameters, such as traffic volume, system capacity, load factor, disturbance allowance and plot radius is also presented.

第三章则从无线规划的角度提出了WCDMA网络的容量问题，通过对WCDMA系统的负荷因子、干扰电平容限以及信噪比的分析计算，阐述了WCDMA系统中容量和覆盖范围及服务质量三者之间的关系，并详细讨论了WCDMA无线规划中业务量、系统容量、负荷因子、干扰容限和小区半径等系统参数的确定。

Parameters of the exciters were optimized to determine the operating point in saturation curves,and obtain the optimal signal-to-noise ratio.

建立了缺陷漏磁场的有限元仿真模型，研究了励磁线圈的形状、励磁电流对检测信号的影响，获得最佳的信噪比。

To improve the measuring accuracy and increase the signal-to-noise ratio in ultrasonic detection of concrete damage, a frequency-modulated ultrasound transmission method was firstly developed.

为提高混凝土超声检测的信号噪声比，提高测量精度，研究脉冲压缩调频超声发射的方法。

Pre-Tertiary oil reservoirs in the South Yellow Sea are old and deeply buried, and there are some difficult problems to be solved in the seismic explorations such as weak reflection energy, low signal-to-noise ratio and poor imaging quality.

南黄海前古近系油气储层时代老、埋藏深，地震勘探中仍存在反射能量弱、信噪比低和成像质量差等难题。

Simulations show the effectiveness and feasibility to reduce the loss of surds and to enhance the SNR (Signal-to-noise Ratio).

该方法在很大程度上抑制了噪声，又减少了语音段清音的损失，提高了信噪比。仿真结果表明了该方法的可行性和有效性。

Only oneA/D converter is needed to complete complex quadrature translation and digital downconversion, get in-phase component and quadrature component in digital field, and also,after intra-pulse compression is done, the signal-to-noise ratio is raised, and inter-pulsecompression is done in digital field, and finally, high range resolution profile is got.Two-step stretch processing method for MMW high-resolution RADAR is presented.

计算并优化了毫米波雷达中频信号带通采样的最佳采样频率，应用现有的集成电路技术实现对中频信号的直接采样、用一个A／D转换器在数字域完成复数正交变换，在数字域完成下变频、获得同相信号和正交相信号、完成对子脉冲的脉内压缩、完成对脉内压缩信号的第二次脉间压缩，从而获得高分辨一维距离像。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。